FM sonography in diffuse liver disease: prospective assessment and blinded analysis

FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.     

Development of a new wound dressing with antimicrobial delivery capability

A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved.     

Statistical analysis of data on airborne asbestos levels collected in an EPA survey of public buildings

Data from a recent EPA study of airborne asbestos levels in 49 buildings occupied by the General Services Administration (GSA) are statistically analyzed. The study focuses on differences between indoor and outdoor levels, and on differences among buildings with no asbestos-containing material (ACM) (6 buildings), buildings with ACM generally in good condition (6 buildings), and buildings containing damaged ACM (37 buildings). Seven indoor samples and a single outdoor sample were collected from most buildings and analyzed by TEM (transmission electron microscopy) using a direct preparation method. No statistically significant differences were detected in asbestos levels between indoors and outdoors or among the three categories of buildings. The average indoor concentration of asbestos was 0.00073 fibers/cc (f/cc) for all fibers and 0.00007 f/cc for fibers 5 microns or longer. The current OSHA occupational standard is 0.2 f/cc for fibers 5 microns or longer as measured by phase-contrast microscopy.     

Use of a Strecker oesophageal stent in the treatment of benign oesophageal stricture

The use of self-expanding prostheses in the management of malignant oesophageal strictures has become well established. The majority of benign peptic oesophageal strictures can be successfully managed using endoscopic or fluoroscopically guided balloon oesophageal dilatation combined with long-term drug therapy, particularly using proton pumper inhibitors. Although endoscopic oesophageal dilatation can be performed on an outpatient basis, it requires repeated hospital visits. There is a small risk of oesophageal perforation whilst cardio-respiratory complications may be encountered during the use of intravenous sedation in an elderly population. The use of a self-expanding Strecker stent in a 98 year old woman with a benign oesophageal stricture is described.     

In vitro selection of human rhinovirus relatively resistant to soluble intercellular adhesion molecule-1.

Variants of human rhinovirus serotype 39 (HRV-39) relatively resistant to inhibition by soluble intercellular adhesion molecule-1 (sICAM-1) were selected by serial passages in HeLa or WI-38 cells in the presence of sICAM-1. Moderate resistance (four- to fivefold increases in 50% effective inhibitory concentrations [EC50s]) was observed after the second passage in HeLa cells and remained constant during six further passages in the presence of 10 micrograms of sICAM-1 per ml. A 7- to 17-fold increase in EC50s was observed in WI-38 cells during passage with 10 micrograms/ml, and reversion to a nonresistant phenotype was not observed after four passages in the absence of sICAM-1. Resistance of a higher degree was obtained by passing HRV-39 in the presence of 100 micrograms of sICAM-1 per ml in HeLa cells (30-fold EC50 increase). The sICAM-1-resistant phenotype was estimated to constitute 1 in 10(4) to 1 in 10(5) PFU of a nonexposed HRV-39 population. Low to moderate levels of resistance to sICAM-1 inhibition emerge readily during in vitro passage in the presence of sICAM-1 and appear to be phenotypically stable.